I sweat a lot when I exercise. After an hour of running at medium intensity (~150bpm avg HR) in 20°C @ 50% humidity, I am literally drenched in sweat. I can wring my clothes and sweat will pour from it. It’s difficult to find clothes that are comfortable to wear for my long trips.
Most of what is use says adidas, puma, the outdoorsman or Columbia on them, and they all say 100% poly. For underwear I use Duluth trading’s armachillo boxer briefs, and I do not have a material list on those.